Prevalence and distribution of root-knot nematode in polyhouse cultivation in Punjab

Protected cultivation is recently picking up in Punjab and elsewhere due to off-season production of crops and high economic returns. The production of crops in polyhouses/net houses is limited by soil borne pathogens. Of the various pathogens affecting vegetable crops root-knot nematode is an economically important pathogen associated with tomato in polyhouses as well as in open cultivation. Surveys were conducted in four districts of Punjab for prevalence and distribution of root-knot nematode. Twenty nine polyhouses were surveyed in these districts of which eighteen were found to be infested with root-knot nematode. In all one hundred and eighteen samples were collected from different sites and of these forty nine were found to be severely infested with rootknot nematode with root gall index (RGI) more than 3. Frequency of occurrence of root-knot nematode in these polyhouses was observed to be 54 per cent.